Guang-Ze Yang, David Wibowo, Jung-Ho Yun, Lianzhou Wang, Anton P.J. Middelberg, and Chun-Xia Zhao*

 

Australian Institute for Bioengineering and Nanotechnology
The University of Queensland
Brisbane, Queensland, Australia

 

Silica nanocapsules have emerged as a novel nanomaterial in recent years as they have attractive properties such as easy encapsulation, controlled release, and protection of various cargoes because of their hierarchical core–shell structure. However, traditional chemical approaches for producing silica nanocapsules have several limitations, such as poor biocompatibility, low encapsulation efficiency, and undesired initial burst release of cargoes. This work presents an alternative and biomimetic approach for the synthesis of oil-core silica-shell nanocapsules under eco-friendly conditions. A pH- and light- sensitive compound (fipronil) is selected as the model cargo and encapsulated inside the silica nanocapsules. More importantly, fundamental research on the encapsulation efficiency, the release behavior of fipronil from the nanocapsules with different shell thickness under different pH (2, 7 and 11), and the protective efficacy to the cargo from degradative environments such as alkali and light were carried out. Our experiments showed that fipronil could be encapsulated inside the nanocapsules with an encapsulation efficiency of nearly 100%, and the release of the active can be precisely controlled by adjusting the shell thickness of the silica nanocapsule. In addition, we found that the release kinetics followed the Higuchi model, enabling us to predict the release of encapsulated cargoes and achieve the synthesis of silica nanocapsules for specific purposes. Furthermore, the silica nanocapsules offer excellent protection to sensitive cargoes against degradation. This fundamental research provides valuable insights into the properties of the silica nanocapsules and enables the design of nanocapsules for various applications which require sustainability, controlled-release, or cargo-protection properties.

 

Biographic Details

Guang-Ze (Daniel) Yang

PhD student

Australian Institute for Bioengineering and Nanotechnology, Australia

Phone: +61 404 496 612 E-mail: guang.yang3@uq.net.au

Research interests: Biomimetic nanomaterials, controlled release, drug delivery

Venue

Room: 
AEB 301